Caster



(No Model.) I

J. R. PAYSON.

OASTER.

, Patented Nov. 22,1881.

illNiTEn- STATES PATENT OFFICE.

JOSEPH R. PAYSON, OF CHICAGO, ILLINOIS.

CASTER.

SPECIFICATION forming part of Letters Patent No. 249,792, dated November 22, 1881.

' Application filed October 6, 1880. (No model.)

To all whom it may concern:

Be it known that I, JOSEPH R. PAYSON, a citizen of the United States, residing in Ohicago, in the county of Cook and State of Illincis, have invented a new and useful Truck and Furniture Caster, of which the following is a specification.

My invention relates to that class of furniture and truck casters in which a series of round balls or globes are inserted between the wheel-plate and the base or screw plate to reduce friction,said balls working in an annular groove; andthe objects of my invention are, first, to decrease the friction of the anti-friction devices themselves, and to simplify and cheapen theirconstruction second,to obtain a more positive and freer movement of the anti-frietion devices,when movingin an annular track or groove, for facilitating the rotation of the bracket and roller upon their vertical axis; third, to enable the use of screws for securin g the base-plate to the furniture without increasing the diameter given it in. the usual construction; and, fourth, to provide a caster with a form of friction devices intermediate the base and bracket plates which will permit of an openin gbetween said friction devices and the pivot of the caster, to provide an access for ascrewdriver to manipulate the screw securing the base-plate to the article of furniture. I attain these objects by devices illustrated in the ac eompanyin g drawings, in wl1ich Figure 1 represents a vertical section of a caster embodying my invention Fig.2, a perspective of the same with the position of. the caster reversed; and Fig. 3 is a perspective of the base or screw plate when reversed from its operative position.

Similar letters of referenceindicate the same parts in the several figures.

A represents an ordinary caster-wheel, pivoted in the usual manner to a bracket-plate, B, and free to revolve in the same. The bracketplate B is circular in form, and atits extreme outer edge is provided with a thin vertical annular rim, b, and with a slight annular groove, 1), inside of and next to the rim 1), and is also provided with a circular opening, 12 through its face, to give access to a screw-driver. The rim 1) and groove b serve as a guide and track for a series of thin disks or an ti-frietion rollers, C. These anti-friction rollers or disks 0 are prevented from falling outwardly by the rim b of the bracket-plate, and may be formed either by casting or cutting from a round rod, or by stamping out of sheet metal, byeitherof which processes they can be made more perfectly round and cheaper than round balls can be made.

D represents a circular base or screw plate .of the same diameter as the bracket-plate, and dis a socket-projection formed upon the upper surface of plate D, and at right angles to the same.

c is an annular-groove, formed in plate D near its periphery, corresponding and coinciding with the groove 1) in plate B. Inside of and nextto the groove 0 is a vertical annular rim, 6, formed upon the lower face of plate D, which, in connection with the rim I), when in the position shown in Fig. 1, forms an annular chamber, in which the anti-friction rollers travel; and c c are screw-holes in plate D.

E is a bolt and pivot-pin, which, passing through openings in plates B and D, is riveted securely at both ends, as shown in Fig. 1, the opening in plate B being large enough to admit of its rotating freely around bolt E. In the position shown in Fig. 1 the plate D is held to the article of furniture by screws in holes c 0 and plate B is held up to its place by bolt E, around which it revolves freely; but when set upon the floor, plate B rests entirely upon the periphery of the friction-disks O. The center of wheel A is placed directly under or inside of theline of disks 0, so that plate B bears evenly upon the disks without any tendency to cant over and bind upon bolt E By means of the thin disks, which occupy but little space laterally, the line of bearing is brought near the periphery of the base-plate, and under or outside of the center of the roller, and a sufficient space is also obtained in the base-plate D, between the rim 0 and the socket-projection d, for screw-holes, to enable the fastening of the plate to the article of furniture, and space is also obtained in the bracket-plate B, inside the driver to the screw-holes in the plate D. This arrangement gives a better bearing upon the line of disks, for an opening to admit a screw- 7 friction-rollers, and obviates the necessity of separating the base and bracketplates for the insertion of screws.

WVhile it is not new to use a series of globes or balls between the base and bracket plates to decrease friction, I am not aware that a series of thin disks have ever before been used in the construction of casters as above described and shown.

Among the disadvantages arising from the use of round balls, which are avoided by the substitution of thin disks, are, first, that the round balls,when travelingin an annular chamber or groove, cause a good deal of friction by rubbing against the sides of the groove and each other, which causes them to twist and turn in opposite directions and impedes their direct forward movement; second, the difficulty and expense of making these balls perfectly round; third, that round balls occupy more space laterally than can be spared in the ordinary construction of casters without sacridoing the space necessary for screw-holes for fastening the base-plate to thearticle of furniture-as, forinstance, around ball threeeigh ths of an inch in diameter occupies at least four times the space laterally that a thin disk-of the same diameter does; fourth, that it is not possible, in the ordinary construction of casters, to carry the line of bearing of these balls'far enough out from the center of the baseplate to bring their center of bearing over the longitudinal center of the bracket-roller, and hence the latter will cant and bear upon the pivot-pin and cause friction. Thin disks travel in an annular groove with less friction than do round balls, occupy much less space laterally, can be applied nearer to theperiphery of the base-plate, leave ample room for screwholes in the base-plate and an opening for a screw-driver in the bracket-plate, and can be made perfectly round with much less skill and expense.

hat I claim, and desire to secure by Letters Patent, is-

1. In a caster, the combination, hereinbefore set forth, with the base-plate and the bracketplate, of a series of friction-disks arranged between and near the peripheries of said plates, and adapted to support the plates from contact with each other.

2. In a caster, the combination, with the base-plate and with the bracket-plate,provided with an annular chamber or groove arranged between and near their peripheries, of a series of disks operating in said chamber or groove, substantially as and for the purpose described.

3. In a caster, the combination, with the floor-roller and with the base and bracket plates, of a series of friction-disks arranged between said plates and revolving in a circle extending outside of and beyond the center of gravity of the floor-roller.

4. As a new article of manufacture, a furniture-caster consisting ofa floor-roller, a revolving bracket-plate, a base-plate, and a series of thin frictioudisks vertically arranged between said plates, said base-plate being provided with an opening between the friction-disks and the pivot of the caster to afford access to the screws securing the base-plate to the article of furniturc.

JOSEPH R. PAYSON.

lVitnesses:

J NO. G. ELLIOTT, JAMES H. 00mm. 

